Core for concrete walls



B. A. KNUDSON.

CORE FOR CONCRETE WAtLS.

APPLICATION FILED MAR. 2, 1921.

1,414,288, Patented Apr 25; 1922 M g/Amw y f UNITE "STATES TJ B ARNEY A;KNUDSON,'0E smv'm Annexat on-um.

-To all whom it may concern:

. Be it known thatI, BARNEY, A. KNUDsoN; a citizen of the United States,residing? at SantaAna, in the county of 'O ran'ge and usefulImprovements in Cores for Concrete walls of whichthe following is aspecification.

forms for concrete walls, the forms preferably'being such as describedin my co-pending application Serial No. 404,217, filed August 17, 1920.

It is the specific object of the invention to.

provide a core which may be readily expanded and collapsed, so thatafter the wall has been formed around the core and between the forms,the core may be readily removed by collapsing the same. 1

The invention will be readily understood from the following descriptionof the accompanyingdrawings, in which Figure 1 ma side elevation showingthe method of using thecores in connection with concrete walls.

Fig. 2 is a transverse section showing a core and form inposition foruse. n .Fig. 3'is a longitudinal-section through acore.

Fig. 4 is a top plan view of the same partly broken away.

- In the drawings I have shown the" cores employed in connection withforms for pouring concrete'walls, the forms preferably comprisinguprights l and 2 received against the respective sides of a part allycompleted wall 3 and supporting upri ht members 4 extending from oneform to e next so as to provide a space into which the concrete formingthe wallispoured; The

uprights 1 and 2 are preferably clamped in position by means of crossmember 5 inter: mediate of the ends of the'uprights and by an uppercross memberfi, provided with a turnbuckle 7 for adjusting the same. The

longitudinally extending members preferably rest upon'lugs 8 and areheld in position by catches 9. V

In order to form hollow spaces within the wall, cores constructed inaccordance with the present invention are received in the space betweenthe form members 4. These core members are shown as cylindrical memhersplaced in upright position in the space I Specification of LettersPatent. Application mansion 2,

its ends overlapping as shown at; 11 -12 State of California,have-.invented newjand p st'ruction. ;A topj13 fits over this core con-I structlon and an- 1 annular depending flange I 1 of the top is boltedas shown at 15.130 It is the object ofthis invention to proe vide a coreemployed 'in connection with late curved upon itself to a circlewithitsv cone. non condemn warns.

i921. Serial No. 449,145.}

sists of a plate 10 'curvedf upon, itselfwith in order'lto Per-cylindrical comma.

one end of the plate 'The top is preferably conical in shape so that anyof'the f Patented; I

between'the form memberspas clearly in Fig.3. Each of't-he coremembers'fconp jmaterialbeing poured, which m ay fall upon the same, willreadilyflow down wardly into the space adapted toreceive the plast cmaterlal, A handle 16. is provided upon the top so .that'by twisting thehandle the top andthe end of plate 10 secured theree j to may be shiftedwith relation to the opa pos1teend'11 of the plate for decreasing thediameter of the cylinder forming the l .75

core. By this arrangement the core may be either expanded or contractedin order to wall when formed.

permit of its insertion and removal from the L A100]: is, preferably,provided forretainf- "ing the core construction in expandedposition,saldlockl ng mechanism comprising a bar 20 adapted to extenddiametrically? v ztcrossQthe opening in; the core and having anupwardlyextended earpivoted' at 21 just above alined openings 18 and19in the overlapplng ends .11 and 12, so that when the 21 will extendthrough the openings and the opposite end of the "bar will press againstthe opposite side of the core and expand a handle upon its upper end foroperating the bar 20. When the handle is. pulled up wardly-the free endof the. bar. 20 swings V I I upwardly out of engage'mentwith the corevbar swings downwardly to a horizontal position the end of thebarflbeyond the pivot and the'other end withdraws fromth'e openings 18and 19,and the core collapses sufli-fl'loo 1 ciently to be drawn out ofthe concrete. The,

pressurefor expanding the core is exertedf' i i against the pivot 21]pushed downwardly.

..Various changesmay be made without de- What isclaimedis:

when-the bar 20 is parting from the spirit of the invention as claimed.

7 extends when in: a horizontalposition and the opposite end of the barbeing adapted to engage the opposite side of the core and core to itsnormal position, and apull rod expanded against I name to thisspecification; exert pressure upon the pivot to expand the connected tothe free end of the bar and extending upwardly through the top, sothat Ithrough the alined'openings to hold thecore the pressure ofthe'concrete.

In testimony whereof BARNEYAJ KNUDsoN-Q g V '30 I have signed 5) ,e

